1. Field of the Invention
The invention relates generally to the fields of autoimmunity and inflammatory bowel disease and more specifically to serological and genetic methods for diagnosing clinical subtypes of ulcerative colitis.
2. Background Information
Inflammatory bowel disease (IBD) is the collective term used to describe two gastrointestinal disorders of unknown etiology: Crohn's disease (CD) and ulcerative colitis (UC). The course and prognosis of IBD, which occurs world-wide and is reported to afflict as many as two million people, varies widely. Onset of IBD is predominantly in young adulthood with diarrhea, abdominal pain, and fever the three most common presenting symptoms. The diarrhea may range from mild to severe, and anemia and weight loss are additional common signs of IBD. Ten percent to fifteen percent of all patients with IBD will require surgery over a ten year period. In addition, patients with IBD are at increased risk for the development of intestinal cancer. Reports of an increasing occurrence of psychological problems, including anxiety and depression, are perhaps not surprising symptoms of what is often a debilitating disease that strikes people in the prime of life.
Unfortunately, the available therapies for ulcerative colitis are limited in effectiveness, and both diagnosis and treatment have been hampered by a lack of knowledge regarding the etiology of the disease. What is clear, however, is that ulcerative colitis is a classification representing a number of distinct disease subtypes that affect the gastrointestinal tract and produce similar symptoms. The heterogeneity underlying UC is reflected in variable responses of UC patients to particular treatment strategies: available anti-inflammatory and steroid therapies are effective in treating some patients with UC, while other patients have disease that is resistant to medical treatment. Methods of diagnosing this medically resistant clinical subtype would be useful since these patients can benefit from early, aggressive treatment prior to full progression of their disease.
Methods for diagnosing the medically resistant clinical subtype of UC would represent a major clinical advance that would aid in the therapeutic management of UC. These diagnostic methods, combined with earlier medical treatment, would provide a patient having medically resistant disease with an alternative to surgical colectomy. Such methods also would advance medical management of UC by identifying a subgroup of patients for whom alternative treatment modalities must be sought. Unfortunately, methods of stratifying UC into medically resistant and medically responsive clinical subtypes are currently not available. Thus, there is a need for such methods. The present invention satisfies this need and provides related advantages as well.